Re: The DOM Debate

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How does it save memory not doing so. The point is in nvda an off screen model is built either way and you have the choice of links etc on one line or not, You also have single key navigation which in your example should work the same either way if you are looking for say edit fields in a form or links to things. The point is that if I were designing a web page for us, as you say the contact us link would be to a sub index also containing the link to the form. I'd also not disable going back as some sites do as in this case unless you are using tabs for pages getting back if you do key a wrong link is not easy to do.

Do I want things to sound like they look?
Well that very much depends on the design. So many forms use tabular organisation then come out and use other ways to put the content of description fields for edit boxes. If I could always force edit boxes to be under their descriptors I'd jump at the chance as otherwise I'd never know which checkbox or whatever went with which choice would I?

So really, I find that often although its good to have a visual image so to speak of what was going on on a site, often you need to think of a web page differently for accessing its silly.
Also those blind from the word go, will no doubt have their own way to mentally arrange things completely different to the sighted. This is why I also get very annoyed at pages where any list of links or whatever are not logical. It may look logical but whoever designed it did not take that logic to the order we would encounter using single key navigation. It can take an age cursoring around a page in the sighted way to find the true layout, and who can remember such a trip in detail? One has to make it simple. Many web designers need to realise the problem of us having no overview as the sighted do when they design pages. I'd much prefer less cluttered pages and have a simple theme and a hierarchical set up where its like a book with indexing myself.
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----- Original Message -----
From: "Christopher-Mark Gilland" <>
To: <>
Sent: Friday, December 01, 2017 8:20 AM
Subject: [nvda] The DOM Debate

For those who may have a bit of a hearing impairment, let me make it very clear. In my subject, I'm saying DOM, D O M, not balm, b A L M. Although some may call DOM the balm. LOL! And here therefore lies the reason for my post this morning. - I fully realize that this is somewhat a subjective topic, and that everyone will have his or her own opinions on the matter. It is therefore my hope, that you, the reader, have an open and civil mind, and observe this question from all angles before making your response statement on list. I do not want to see this grow to a heated war debate. Anyone who would like to publish this on their website, or wherever is welcome to do so as long as you give credit back to me.

First off, what is DOM?

DOM, Document Object Model, without getting too technical, is one way in which assistive technology such as screen readers obtain information from one's computer screen. When we load a website in our browser of choice, for example, some screen readers use the DOM functionality to draw a representation of the content on the screen.

So, what does this mean to us non-techies?

Put simply, though I am not particularly sure of the exact workflow which occurs behind the scene, what I can tell you is this. Often times, more than not, this approach requires the assistive technology sitting in between the user and the web browser to redraw, as some would say, the entire HTML content in completion. The reason that the word "redraw" is used is because essentially, this is exactly what is happening.

Once a website is loaded, a certain amount of memory is allocated aside where the website in question may be rendered. There are a few advantages to this, however there are also some huge setbacks.

Beauty and the Beast

One of the advantages which probably appears to be fairly obvious from an outsider's perspective is that this will allow assistive technology to use certain methods to gather the web content and then present the material in an easy, robust, and sensably accessible manor. As the writer of this post, let me assure all of you... I definitely see the side of this argument.

Here's a practical example of DOM.

Let's assume, for just a moment, that you have loaded a website in the browser of your preference, be it Firefox, Internet Explorer, Chrome, etc.

On this particular page, there are links which visually appear as horizontal tabs extending across the top of the page. These tabs include the following:

a.. Home
b.. About Us
c.. Blog
d.. Shop
e.. Support
f.. Contact Us

To fully understand how this works, I encourage you to read the following part of this e-mail by using your down arrow key, and reading line by line individually. Here is what you will see. Remember before I go any further with this, all of these links visually appear as one strip of horizontal tabs running across the top of the web page.

Link Home
Link About Us
Link Blog
Link Shop
Link Support
Link Contact Us

Here's another example.

You have a short form on a website. This form asks for your first name, your last name, and your e-mail address. Here's how DOM most likely would reinterpret this. Again, please read this line by line.

Please fill out the following form so we may keep in touch.

First name
Last name
Submit button
Clear form button.

First example without DOM

Read this line by line, and make sure this window with my message is maximized before doing so.

Link home, Link About Us, Link Blog, Link Shopt, Link Support, Link Contact Us.

Second example without DOM

Please fill out the following form so we may keep in touch.

First name Edit
Last name Edit
E-mail Edit, Submit: button, Clear form: Button.

The difference

As you can see in the above four illustrations, the first two examples were rendered in such that each link/form control was on its own line. This is why I asked you to read line by line, as doing a say-all, you never would have most likely caught this. So, in other words, let's make this really easy in plain english.

Refer back to my very first example where we had the tabs which are being represented as hyperlinks. As you recall, I said that they all went horizontally from left to right across the top of the page.

The problem is, DOM renders each element, for lack of better word, as its own separate item. For this reason, each element is on its own dedicated line of text. This is why each link is seeming to appear on its own line by itself. The truth is, these links in all actuality are not on multiple lines. They are actually expanding across the entire marginal width of the screen. Are you starting to see where this could be a potential problem?

The second example is slightly less annoying, however the point still stands in existance.

We have a form. If you've ever seen how a form generally looks on a print sheet of paper, you'll note that most form field labels such as first name, last name, etc. go down the left side of the sheet of paper. Then, horizontally aligned beside these field labels is the data value.

For example, I might have a form printed out which I sign for a Hippa release at my doctor's office. The first field may say, "Name". Out to the immediate right of this will be either a line, or a box. It just depends on how the form is designed, but the over all point is, there will be a second column to the immediate right of where it said, "First name". This is where I would write, "Christopher (Middle name) Gilland. Obviously, some of you may know my middle name, but for privacy sake, I'm not including it here.

Given how the above physical print paper illustration is formatted, as most forms online or not would be, does it really make sense to have the form field, then the data directly below? No. It doesn't.

Look at my above second example without DOM. Notice that the edit box for all three fields is now actually rendering exactly as it would be visually on the screen. The boxes are to the immediate right of the fields, on the same line. Doesn't that just naturally feel better in your mind, and make more sense? It definitely should to most people.

Finally, we have both the submit, and the clear vbuttons.

Does it make sense to you that they'd both be virtically stacked one on top of the other? It certainly doesn't to me! In fact, to me, I'd even go so far as to say it seems absolutely gross! Maybe I am more a visual learner, but even if I wasn't, this doesn't logically compute. However, this is exactly how DOM is rendering it... One button, and one element per line.

Helping the sighted to guide you

So why is this such a vbig deal? Call me a perfectionist, but let's assume for just a moment that you're on the phone with a customer service representative. They tell you to click the contact us tab located in the upper right corner of the page. This would be a very poor website design, and to any web debvs on here, please for the love of god, take this in consideration! I can't tell you though how many times I've seen this. A web designer will put a contact link at the top of the page which has a form to e-mail them. Further down the page, they have another contact link within the actual main body's content. The difference however is, in this second link, though named identically the same thing, "Contact Us", this second link doesn't direct the visiter to a contact form, but instead gives a phone number, fax number, and possibly a postal address. Totally unacceptable in my view! All this should be consolidated on the one contact page at the top of the screen. This however still proves my point, and like I said, I've seen this more times than I could count, and would gbe rich if I had a dollar for every time I have. OK, so, you now arrow through the page, or do an NVDA find to locate the Contact link. Heck, you might even do NVDA+F7 to bring up your links list. And believe me, though I'm directing this more as an NVDA thing, NVDA isn't the only screen reader which can use the DOM method. JAWS, for example, is incredibly! and I do mean, incredibly! notorious for this. Now, think about this a minute with this really convoluted scanareo regarding the contact link. - How are you going to know which contact link to press enter on to open the contact form, if you're in DOM navigation? Exactly! - You won't. It would be hit and miss.

Now, let's take this same situation without DOM mode.

In this environment, for lack of better word, you would observe both via audible speech, as well as via braille output if you have a display, that the first "Contact us" link is on the far right edge of the screen. You'd know this as you'd see the other links like Home, About us, Blog, etc. on the same line but to the immediate left before it. Does this make sense what I'm saying?

The bottom line

Regardless if you choose to use DOM or not is not something anyone should decide for an individual. If you are coming from a screen reader like JAWS as I have, you definitely may find turning off DOM navigation to be extremely awquard at best. I'd even go as far as to say that it may drive you absolutely crazy at first, and make your web browsing experience seem dreadful. I would however seriously encourage people to at least give it a try for a few days without DOM navigation. Inevitably, if you're not used to it, it's going to take some getting used to, however if you're anything like me, I feel that eventually, you will really start to see the benefits of not using DOM. DOM is great in my opinion, don't get me wrong, but if you want, or need in a mission critical environment to have an exact representation of the content, then fact is fact, you're not going to get it with DOM mode, end of the story, it's just not gonna happen, period. You might as well just accept it. The other thing to also realize is, you are taking up unnecessary memory/processor power to render things differently as an offline model. Granted, OK, it may not be much, but that's not the point. It's still taking up what to some would be considered as unnecessary resources.

What are your thoughts?

Do you use DOM? If not, I'd be interested in your reasons why not.


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